Unit 4.2 Your Turn

Waves do three main jobs that shape the coastline. Select the correct three.

• deposit

• transport

• longshore drift

• abrasion

• erode

Describe three ways in which waves erode rock.

• hydraulic action

• solution

• deposit

• abrasion

• constructive wave

X and Y are two pebbles made from the same rock. Which one has been in the water longer?

• X, because it has nicer edges.

• Y, because the color is lighter

• Y, because it is smother since the edges have been worn down.

• Y, because it was deposited on the beach.

What process made Y so smooth?

• transport

• hydraulic action

• solution

• attrition

Groynes are barriers of wood or concrete, on a beach. Why were they built?

• to make sure the waves don't damage the homes close the beach.

• to stope the beach from eroding.

• to give visitors to the beach a place to sit.

• To help the economy of the city.

In which direction is the longshore drift heading?

• from the northwest the southeast,

• from the southeast to the northwest

• from the southwest to the northeast.

• from the northeast to the southwest.

The drawing shows part of an island. The prevailing wind for the island is blowing. From which direction does it blow.

• Southeast

• Southwest

• Northeast

• Northwest

There is no beach at A. What do you think is the reason?

• It is too close the cliff.

• It is not sheltered enough.

• the surf is too strong.

• The gods didn't want a beach there.

There is a good beach at A. What is the reason?

• B is sheltered so sand is deposited.

• B is a perfect place for a beach so sand is deposited.

• People need a place to sunbath so sand is deposited.

• There isn't a cliff there.so sand is deposited.

Where might the sand at B have come from?

• From a sand quarry owed by the city.

• From the erosion of rocks; it would be difficult for them to have come from A.

• From the transport of rocks as a result of the erosion of the land behind the beach.

• From the erosion of rocks; at least some would have come from the rocks at A.